TY - JOUR
T1 - Influence of photochemistry on the marine biogeochemical cycle of dimethylsulphide in the northern North Sea
AU - Hatton, Angela D.
N1 - Funding Information:
This work was supported by a Natural Environment Research Council Fellowship (GT5/97/6/MAS). I thank Axel Miller (UHI) and Geoff Smith (QinetiQ, formerly DERA) for the use of their DOC and DMS data, and David Meldrum, Mike Burrows and Mark Inall for their help and advice with rate calculations, light data and statistics. Finally, my thanks to the officers, crew and fellow scientists onboard the R.R.S. Discovery 241.
PY - 2002
Y1 - 2002
N2 - Shipboard experiments were conducted in the northern North Sea to assess the rate of removal of dimethylsulphide (DMS) and the rate of production of DMSO due to both UVB and UVA/visible light. Experiments were conducted using 0.2-μm filtered seawater and natural light conditions. The DMS photolysis rate constant was determined to be between 0.03 and 0.07 h-1, and initial photolysis rates were between 1.3 and 2.5 nmol dm-3 d-1. Using these rates, the in situ profiles for downward irradiance, and the DMS concentration in the water column, a photochemical turnover rate constant of between 0.1 and 0.37 d-1 was determined for the upper 20m of the water column, with a photochemical turnover time of between 2.5 and 9.5 days. DMSO photoproduction rates were up to 1.20 nmol dm-3 d-1. Furthermore, results indicate that under UVA/visible light most of the DMS is photo-oxidised to form DMSO, whereas under UVB radiation DMS may be removed via a second photolysis pathway.
AB - Shipboard experiments were conducted in the northern North Sea to assess the rate of removal of dimethylsulphide (DMS) and the rate of production of DMSO due to both UVB and UVA/visible light. Experiments were conducted using 0.2-μm filtered seawater and natural light conditions. The DMS photolysis rate constant was determined to be between 0.03 and 0.07 h-1, and initial photolysis rates were between 1.3 and 2.5 nmol dm-3 d-1. Using these rates, the in situ profiles for downward irradiance, and the DMS concentration in the water column, a photochemical turnover rate constant of between 0.1 and 0.37 d-1 was determined for the upper 20m of the water column, with a photochemical turnover time of between 2.5 and 9.5 days. DMSO photoproduction rates were up to 1.20 nmol dm-3 d-1. Furthermore, results indicate that under UVA/visible light most of the DMS is photo-oxidised to form DMSO, whereas under UVB radiation DMS may be removed via a second photolysis pathway.
UR - http://www.scopus.com/inward/record.url?scp=0036083616&partnerID=8YFLogxK
U2 - 10.1016/S0967-0645(02)00070-X
DO - 10.1016/S0967-0645(02)00070-X
M3 - Article
AN - SCOPUS:0036083616
SN - 0967-0645
VL - 49
SP - 3039
EP - 3052
JO - Deep Sea Research Part II: Topical Studies in Oceanography
JF - Deep Sea Research Part II: Topical Studies in Oceanography
IS - 15
ER -
